The transformation kinetics of alpha and beta plutoniunn were determined by using a fluid displacement technique. The rate of formation of the alpha phase from the beta phase was determined after beta heat treating and allowing the sample to transform isothermally in the alpha range. Isothermal reaction curves were obtained from --78 to +90 d C. A time- temperaturetransformation curve showed the maximum rate of transformation to be approximately --20 d C. The beta phase did not transform completely to the alpha when the transformation was allowed to take place isothermally. A relationship between the fraction untransformed beta and the transformation temperature has been established. Isothermal reaction curves and a time- temperature-transformation curve of the alpha at 200 deg C an - BETA transformation were obtained. Portions of the timetransformation curves of the BETA at 200 deg C an alpha transformation of four purities were plotted. The effects of beta heat treating times and temperatures were studied. Photomicrographs of a specimen having transformed from the beta to the alpha phase at different rates of transformation are presented. (auth)

The idea of ''antiparticles'', as is well known, originated with Dirac, who in establishing the relativistic equations for the electron noted that besides the solutions corresponding to ordinary electrons there were also ''unwanted solutions'' corresponding to particles of electronic mass but of charge +e instead of the electronic charge - e. The discovery of the positron by CD Anderson offered a brilliant experimental confirmation of Dirac's prediction and gave the first example of an ''antiparticle.''

This is the monthly report for the Hanford Laboratories Operation, March, 1958. Metallurgy, reactor fuels, chemistry, dosimetry, separation processes, reactor technology, financial activities, visits, biology operation, physics and instrumentation research, and employee relations are discussed.